1. Field of the Invention
The present invention generally relates to a trolley stop for an overhead track system to prevent the trolley from rolling off the end of a track when a switch element is not in operative relationship to the end of the track in which the stop is spring biased to its operative position and is cammed toward its inoperative position when either of the track switch elements are operatively associated with the end of the track.
2. Description of the Prior Art
My prior U.S. Pat. No. 4,014,269, issued Mar. 29, 1979 discloses a gravity operated type of trolley stop used in an overhead track system and my prior U.S. Pat. No. 3,739,727, issued June 19, 1973 discloses an automatic switch for overhead track systems. Overhead track systems and switches incorporated therein are well known in various industries and various prior patents disclose such structures including the above-mentioned patents and the prior art of record in those patents. In addition, the following U.S. patents are relevant to trolley stops:
U.S. Pat. No. 301,119, H. S. Haskins et al. PA1 U.S. Pat. No. 989,899, H. L. Ferris PA1 U.S. Pat. No. 891,493, R. B. & W. Louden PA1 U.S. Pat. No. 967,869, J. C. Fitzgerald PA1 U.S. Pat. No. 1,155,214, E. E. Conrad PA1 U.S. Pat. No. 1,878,605, O. C. Schmidt et al.
The above patents disclose various types of trolley stops but none of them discloses a structure equivalent to the present invention.